Abstract

Yeasts are unicellular eukaryotic fungi, Saccharomyces cerevisiae being the most representative species both in laboratory and in industry. In nature, yeasts are abundant in the skin of fruits
and grains. In fact, fruit juices or aqueous solutions of cereals provide excellent broths for yeast cultivation and traditional
beverages production. The use of yeast by humans to process food and alcoholic beverages is traditionally marked as the primary
inventive step of biotechnology, dating back several millennia. At present, these microorganisms have increasing fundamental
and industrial importance in scientific, food and pharmaceutical disciplines. The use of yeast as a model organism for laboratory
and modern biotechnology has led to the development of synthetic and industrial media for optimal cultivation of these microorganisms
in ‘batch’, ‘fed‐batch’ and ‘continuous’ culture systems.

Key Concepts

Yeasts are unicellular eukaryotes.

Yeasts are grown on solid growth media or in liquid broths.

Batch and continuous culture systems are available for small‐ and large‐scale yeast culture.

Saccharomyces yeasts are behind traditional procedures making fermented foods and beverages such as bread, beer or wine.

Molecular biology tools enable the production of numerous biotechnological products by yeasts.

Fidalgo
M
,
Barrales
RR
,
Ibeas
JI
and
Jimenez
J
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